Antiseptic actions against soy sauce were compared of the diethyl esters of dibasic acids such as malonic and succinic acids, and their halogen and thiocyano substitutes. It was also found, in this case, that the action was strongest in the thiocyano substitutes, followed by halogen substitutes and esters of original fatty acids.

Antiseptic action against soy sauce was found to be increased by the substitution of thiocyano group and halogens in fatty acids, and the order of the action becomes increasingly stronger from esters of fatty acids to their halogeno and thiocyano substituted derivatives.

By the condensation of acetone with 2-methyl-2-formylcyclohexanone, using the method of Wilds and Djerassi for the synthesis of cyclodienone by nuclear methyl substitution, 2-keto-4a-methyl-2, 4a, 5, 6, 7, 8-hexahydronaphthalene, b.p.4 129° (semicarbazone, m.p. 202° (decomp.)) was synthesized. It was found that this compound underwent two kinds of dienone-phenol rearrangements. By the application of fuming hydrochloric acid or 50% sulfuric acid, the nuclear methyl underwent rearrangement to give 4-methyl-2-tetralol, m.p. 105°, while the action of acetic anhydride and sulfuric acid resulted in the rearrangement of the hydrogenated ring to 4-methyl-1-tetralol, m.p. 86°.

1) Comparative studies of antibacterial activities in vivo were made of the esters, thioesters and acid amides of p-nitrobenzoic acid and the esters of m-nitro- and p-chlorobenzoic acids.2) Chloro- or nitro-phenyl ester of p-nitrobenzoic acid is fairly active against streptococci and pneumococci type I, but the esters of m-nitro- and p-chlorobenzoic acids do not possess such actions.3) The esters of p-nitro-monothiobenzoic acid possess only a weak action against streptococci and pneumococci but 4-nitrophenyl ester alone possessed enough action to inhibit growth of Mycobacterium tuberculosis (avian type, Takeo strain) in vitro at 1:250000 dilution.4) The anilides of p-nitrobenzoic acid are practically ineffective but 2-p-nitrobenzamino-4-methylpyrimidine and 2-p-nitrobenzamino-thiazole are both effective, the former being almost as effective as sulfapyridine.5) All the compounds tested were synthesized by the ordinary method.

The hot aqueous extract of 40 kinds of crude drugs were tested as to their antibacterial action against Staphylococcus aureus, using bouillon dilution method. Digests of Rhizoma Coptidis, Radix Scutellariae, Cortex Paulowniae, Semen Euryales, Herba Salicariae and Radix Gei japonici were found to have the most strong action, being effective at or above 1:960 dilution of the original drug. These were followed by Rhizoma Rhei, Rh. Karadaiwo, Rh. Rumecis japonici, Folium Uvae Ursi, Fol. Vitis-Idaeae, Herba Pirolae, Herb. Plectranthi and Herb. Tanaceti, which were effective up to 480 dilution.

Acetone extracts of 50 kinds of crude drugs were tested as to their antibacterial action against Staphylococcus aureus, using the bouillon dilution method. It was found that Cortex Mori radicis and Semen Euryales were the most strongest, being effective up to 12800 dilution, followed by Galla, Gallae halepenses and Folium Eucalypti, which were effective at 6400 dilution; Rhizoma Coptidis, Rh. Karadaiwo, Radix Scutellariae, Cortex Paulowniae and Fructus Evodiae, at 3200 dilution; and Cortex Magnoliae obovatae, Rhizoma Galangae, Semen Paeoniae, Radix Liquiritiae, Herba Rutae and Herba Salicariae, at 1600 dilution.

Antibacterial action against Staphylococcus (Terashima strain) was examined with 1000 plants collected in the Gumma Prefecture, comprising 150 families and 587 genera. The distribution of antibacterial action was discussed from the point of plant classification. Those showing effective actions were found to be centered in certain genera which seemed to show that antibacterial action was approximately specific to each genus. Those possessing antibacterial action were found in the following: Compositae, Caprifoliaceae, Labiatae, Verbenaceae, Borraginaceae, Convolvulaceae, Ericaceae, Pirolaceae, Cornaceae, Umbelliferae, Hydrocaryaceae, Guttiferae, Vitaceae, Rutaceae, Rosaceae, Saxifragaceae, Magnoliaceae, Berberidaceae, Lardizabalaceae, Ranunculaceae, Nymphaeaceae, Polygonaceae, Juncaceae, and Polypodiaceae.

Distribution of antibacterial action in various parts of plants was examined and it was found that the action became weaker in the order of flower, leaves, fruit and seeds, whole plant, stem and root. Antibacterial actions were found to be present more in flowers possessing aroma, in woody stems and in the roots of perennial herbs.

In connection with the antibacterial action of flowers, anthocyan was extracted by methanolic hydrochloric acid, but this was found to be practically ineffective. Variation in the antibacterial action according to the time of collection was discussed and it was found that the action was approximately parallel to the growth of plants. An approximately parallel relationship was found to exist between the antibacterial action and anthelmintic or insecticidal action of a plant.

Antibacterial action against Staphylococcus aureus or Escherichia coli and insect repellent action against Attagenus piceus were compared with compounds chiefly composed of the chloro derivatives of phenoxyacetic and salicylic acids. Results showed that these two actions were approximately parallel, endorsing assumptions earlier held by the authors. The relationship between the number of chlorine atoms or position isomerism in the compound and efficacy are discussed.

Antibacterial action against Staphylococcus aureus and E. coli, and insect repellent action against Attagenus piceus were compared with p-chlorobenzenesulfonamide, its derivatives and chloro derivatives of phenylguanidine. An approximately parallel relationship was found to exist between these two actions. In guanidine derivatives, efficacy differed according to the position of chlorine atom, being strong in meta and para derivatives, while that of ortho derivative was weaker. It was also found that the compound was effective against E. coli as long as the hydrogen in the imide group was not substituted.

Investigations were carried out on the Hinoki Leaf Oil, an essential oil from the leaves of Chamaecyparis obtusa, and a new component, d-terpinyl acetate, was found besides the well-known components of pinene, limonene, bornyl acetate, sesquiterpene and sesquiterpene alcohol. Hinokic acid, m.p. 166°, contained in the acid portion, was founc to correspond to C15H22O2 from its analytical values, rather than the previously proposed C15H24O2. The acid is monobasic, contains two double bonds and gives a tetrahydro compound of m.p. 153°. It was assumed that the chemical structure of hinokid acid would be a bicyclic sesquiterpene-carboxylic acid possessing two double bonds. It was also observed that this acid was effective in inhibiting the growth of Mycobacterium tuberculosis (avian type) in vitro, at about 1:10000 dilution.

Up to the present, phloroglucide has chemically been found in the rhizome and stipes of Dryopteris crassirhizoma Nakai and D. lacera O. Kuntze, in Japan. It was also recognized by a histochemical method in the rhizome and stipes of Dryopteris Bissetiana C. Christensen var. sacrosancta H. Ito, D. cycadina C. Christensen var. melanolepsis Nakai, D. cystolepidota C. Christensen, D. erythrosora O. Kuntze, D. pseudoerythrosora Kodama, D. Sieboldii O. Kuntze, D. tokyoensis C. Christensen, D. uniformis Makino and D. varia O. Kuntze. The method of detections was as follows: Powder of rhizome and stipes was digested for two days with carbon disulfide, the digest solution filtered and evaporated. The residue was extracted with 5% barium hydroxide, filtered, acidified with 5% hydrochloric acid, and the precipitates extracted with petroleum ether. The crystals obtained melted at 156°, corresponding to that of flavaspidic acid. A few drops of Ehrlich-Koziczkowsky's reagent added to these crystals under the microscope will allow observation of their change to reddish crystals.

The macro- and microscopic features of the rhizomes and stipes of several ferns containing phloroglucide were studied. Pharmacognostic studies and the important differences, such as the number of sclerenchimatic layers, are discussed.

Reactions were examined between p-nitrophenylsulfenyl chloride and 2-amino-4-hydroxy-6-methylpyrimidine (I), 2-amino-4, 6-dihydroxypyrimidine (II), 2, 4-dihydroxy-6-methylpyrimidine (III) and 2, 4, 6-trihydroxypyrimidine (IV). In the cases of (I) and (II), substances assumed to be 2-(p-nitrophenylsulfenylamino)-pyrimidines were formed which, when heated with acetic anhydride, did not undergo rearrangement. In the cases of (III) and (IV), the compounds formed were 4-nitrophenyl-pyrimidyl-5′-sulfides which, when oxidized, yielded the corresponding sulfone compounds.

Various sulfone compounds possessing pyrimidine nucleus were synthesized by the reaction of 2-amino-4-methyl-6-chloro-, 2-amino-4-chloro-, 2-chloro-4-methyl-6-chloro- and 2, 6-dichloro-4-methyl-pyrimidines and sodium p-toluenesulfinate and p-acetamino-benzenesulfinate.

Distribution of nitrogen was examined by the van Slyke method with the protein portion of Venerpis Semidecussata Reeve collected during the spring and winter. There was no remarkable difference found in the amount between spring and winter shellfish except that of arginine which increased slightly during the spring. The samples from the winter one was hydrolyzed, from which were isolated tyrosine, cystine, leucine, phenylalanine, valine, alanine, glutamic acid, aspartic acid, arginine, histidine and lysine, as well as proline from the non-amino nitrogen. By using small amounts of the protein, the presence of tryptophane and methionine was recognized and quantitatively determined. The examination of hydroxyamino acids was negative by periodic acid.

Reports on the aurate of glycocoll-betaine have been made by E. Fischer, R. Willstätter, M. Becker and H. Stoltzenberg, but salts of various gold content are obtained according to the manner of recrystallization and their compositions are not uniform. The authors examined X-ray powder photographs of the aurates and found that when recrrystallized from water, it forms mixed erysatls in the ratio of 4:1 and 3:1 of glycocoll-betaine aurate vs. glycocoll-betaine, and the decomposition point became lower.

Caronamide, i.e. benzylsulfonamide-benzoic acid, was obtained by the condensation of benzylsulfochloride and p-aminobenzoic acid under the presence of alkalis. These materials were all led from toluene and were obtained without much difficulty. The heating in the final condensation was likely to bring about decomposition of the chloride and the reaction was therefore carried out at a room temperature with the alkali as a condensation agent.

1) It was found that ethyl methylolmalonate was formed in a good yield by the reaction of ethyl malonate and formalin at below 40° under the presence of sodium acetate. This compound is a colorless, slightly viscous oil, easily soluble in organic solvents and insoluble in water. It is impossible to purify this compound as it decomposes by distillation.2) Ethyl methylolmalonate is dehydrated by a small amount of diethylamine and changes to the already-known ethyl methylenemalonate.3) Ethyl methylolmalanate and ethyl malonate condense easily under the presence of sodium ethoxide to form tetracarbethoxypropane. This method is valuable for the new synthetic method to obtain the latter.

Antiseptic power against soy sauce was tested with the following eight compounds: 6-Methyl-, 6-ethyl, 6-n-butyl-, 6-n-amyl, 6-isoamyl-, 6-n-hexyl-5-ethyl- and 5-n-propyl-7-hydroxycoumarins. 6-n-Butyl compound was found to inhibit the growth of mold in ca. 0.01% strength during the 50-day test period but others only showed a very weak antiseptic action at 0.001-0.01% concentration.

1) Three methods of industrial syntheses of rac.-N-methyl-ephedrine were examined.2) Propiophenone, the material for this synthesis, was found to be obtained in a pure state and in a good yield by the Grignard reaction of benzonitrile and ethyl bromide.3) Dimethylation of rac.-nor-ephedrine was found to proceed in a good yield by the use of formalin, formic acid and sodium formate.

It was found that pyridine is formed by the catalytic vapor-phase oxidation of α-picoline. Pyridine was obtained in 3.4-6.2vol.% yield from α-picoline by passing through a mixture of α-picoline and air over the catalyst of nickel oxide-kaolin at 180-250°. This catalyst, however, has a very short life and looses its activity in only 20-50minutes, becoming useless. Vanadium pentoxide-pumice catalyst was found to be excellent by long use, and the yield of pyridine did not decrease after repeated use over a long period of time. By the use of this catalyst, pyridine was obtained in 8-10vol.% yield at a temperature of 465-475°. Carriers used were kaolin, kieselguhr, alumina, pumice and asbestos. Molybdenum oxide also gave about the same yield of pyridine when used as a catalyst but it also had a very short life. Tungsten, manganese and chromium oxides also were able to produce pyridine but in a very small amounts. Pyridine was not formed when cupric oxide and lead chromate were used as catalysts. Demethylation by passing through a mixture of α-picoline and hydrogen gas over nickel catalyst was not successful. Pyridine thus formed was quantitatively determined as perchlorate.

Studies were made on the method of quantitatively determining the content of pyridine in a mixture of pyridine and α-picoline. To 1cc. of this mixture, 5cc. of butanol was added as a solvent, cooled with ice-water, and 72% solution of perchloric acid was added dropwise with methyl orange as the indicator. The crystals of pyridinium perchlorate thus formed is in direct proportion to the concentration of pyridine in the sample and, between 100-20% of pyridine, the yield of perchlorate was in an average of 97.4% of the theoretical value. The amount of pyridine in the original sample is calculated by: x=100w/2.17 or x=46.1w where w is the weight (in g.) of perchlorate obtained by actual determination and x is the concentration (in %) of pyridine in the original sample. Ethanol, benzene, toluene, gasoline (b.p. 150-160°) and isoamyl alcohol were also used as solvents but were found to be unsuitable for quantitative determination.

It had been found that isofarnesenic acid, synthesized from citronellal, showed a remarkably growth inhibitory action against culture test of avian type tubercle bacilli and also showed a strong antagonism against benzoic acid of oxydase system oxidating benzoic acid, so that dehydrofarnesenic acid, possessing one double bond more than the above compound and ionylideneacetic acid, closely related to vitamin A, were synthesized and their growth inhibitory actions against avian type tubercle bacilli were tested. Both these compounds possessed far weaker action than that of isofarnesenic acid.

By the condensation of p-nitrobenzenesulfin chloride with 2-acetaminothiazole or 2-acetamino-4-methylthiazole, 2-acetamino-5-(p-nitrobenzenemercapto)-thiazole derivatives were obtained instead of 2-acetamino-5-(p-nitrobenzenesulfoxy)-thiazole derivatives. Similar reactions occurred in the case of benzenesulfin chloride, p-toluenesulfin chloride and p-bromobenzenesulfin chloride.

2′-Aminothiazolo-(5′, 4′: 5, 6)-hydrocinchonidine was found to be effective, both in acid and ammonia processes, as an inhibitor of fogging in photographic emulsions. In order to study its effective structure, 6-, 5- and 8-aminoquinolines and p-aminophenylsulfon-amide were thiocyanated by potassium thiocyanide and bromine to 2′-aminothiazolo-(5′, 4′: 5, 6)-quinoline (II), m.p. 284° (decomp.), 2′-aminothiazolo-(4′, 5′: 5, 6)-quinoline, m.p. 270-272° (decomp.), 2′-aminothiazolo-(5′, 4′: 7, 8)-5-thiocyanoquinoline, m.p. 206-208° (decomp.), and 2-amino-6-sulfaminobenzothiazole, m.p, 278-279° (decomp.), respectively. As a result of their emulsion tests, (II) and its acetate were found to be effective.

The authors reëxamined preparatory process of pyridine given by Example 4 in F. P. 681839 but unfortunately pyridine could not be obtained. Under an entirely different notion, acetylene and ammonia were condensed with CdO-Fuller's earth as a catalyst, its reaction solution fractionally distilled and a portion boiling out at b.p. 125-130° (chiefly α-picoline) was collected. This was passed over a catalyst of V2O5-pumice stone (containing a small amount of MoO3, Cr2O3 and WO3) at a temperature of 500°C, and pyridine was obtained in a good yield.

Numerous studies have been made on the constituents of Piper Bette L., from Thailand, Philippines, Java, India and Formosa. However, the substances contained, specific gravity and yields differ greatly in each area. Components other than chavibetol, especially the content of chavicol, were only reported by Eijkmann from a Javanese plant, and chavicol has been found in no other plants. The authors obtained a large amount of the leaves of Piper Bette growing in Formosa, and detected chavicol, chavibetol and allylpyrocatechol as their components.

After a general analysis of the leaves of Bryophyllum calycinum Salisb., its components were examined and confirmed the presence of calcium malate, succinic acid, quercetin and rutin. It was assumed that quercetin was obtained by a decomposition during processing from rutin.

“Pinenilanaldehyde” was isolated as one of the constituents of the oxidation products of α-pinene with chromyl chloride. On oxidation of α-pinene, transformation occurs in the pinane ring to give an aldehyde which contains an isocamphane nucleus. The aldehyde is readily autoxidized to dl-isocamphenilanic acid, m.p. 118-118.5°, which can also be obtained from the aldehyde by oxidation with permanganate and identified by comparing with the same acid synthesized from camphene. No difference in the m.p. of the acids were observed both before and after recrystallization from acetic acid or methanol, the acid being proved to be isocamphenilanic acid. Consequently, the aldehyde must be isocamphenilanaldehyde, which gives a semicarbazone of m.p. 188-189°.

A ketonic substance found in the oxidation products of α-pinene with chromyl chloride was isolated confirmed as d-pinocamphone, C10H16O, which gives a semicarbazone of m.p. 228-229°, a p-nitrophenylhydrazone of m.p. 174-175°, a dibromide of m.p. 97-98°, and a liquid oxime. When oxidized with ferric chloride in an acetic acid solution, the ketone gives carvacrol andpinocamphoric acid, m.p. 182-183°, by permanganate oxidalion. From physical and chemical points of view, the ketone and its derivatives appear to be a mixture of some of its stereoisomers. The ketone was also identified by comparing with the same compound synthesized from α-pinene nitrosochloride by Wallach's method.

d-Pinocampheol, C10H18O, was obtained from d-pinocamphone by reduction with metallic sodium and alcohol. This reaction is reversible, pinocampheol yielding pinocamphone by oxidation with bichromate and sulfuric acid. The alcohol, when heated with potassium bisulfate, undergoes dehydration to give α-pinene which was confirmed by its nitrosochloride, m.p. 105-106°, and by pinic acid, m.p. 135-136°, obtained from the products of permanganate oxidation. Pinocampheol methylxanthate, m.p. 61-62°, also decomposes into α-pinene by pyrolysis. From physical and chemical grounds, this alcohol appears to be mixture of some of its stereoisomers, e.g. pino-, isopino-, neo-, or neoiso-pinocampheol. On oxidation of α-pinene with chromyl chloride, addition, hydration and dehydration seem to occur on the double bond and results in the formation of pinocamphone as the normal reaction product, and partial isomerization of α-pinene to camphene proceeds prior to the formation of camphenilanaldehyde.

A mixture of crude α-picoline, b.p. 127-131° (containing 5.5-14.5% pyridine), and air was passed over a catalyst of V2O5, MoO3, WO3 or CrO3, and the amount of pyridine formed by each catalyst was examined. Pumice stone was found to be good as a carrier, rather than asbestos or kieselguhr. Both MoO3 and WO3 were found to have a very short life by themselves and give poor yield of pyridine. CrO3 also gives a very minute amount of pyridine. These substances, however, impart an excellent property to V2O5 as a catalyst when added in a very small amount as a promotor. For example, a mixed catalyst of V2O5 containing one or two of Cr, Mo and W in about 10% of the former, was proved to be active in a temperature range of 450-550°, and gave a good yield of pyridine. A catalyst containing all three substances active in a temperature range of 400-600°. The formation ratio of pyridine was found to be 28-30° vol.% of the original material (disregarding the amount of pyridine contained originally). When calculated with substraction of unreacted picoline from the original material, pyridine formation becomes 37-40 vol.%. In connection with actual pyridine preparation, the authors also studied comparative difference of the forms of the catalysts and the state of reaction by the difference in temperatures.

1) 1-Dialkylaminomethyl-3-methyl-6, 7-methylenedioxyisoquinoline (I), bis-(3-methyl-6, 7-methylenedioxy-isoquinolyl (1)-methyl)-alkylamine (II) and tri-(3-methyl-6, 7-methylenedioxy-isoquinolyl (1)-methyl)-amine (III) were prepared by treating 1-chloromethyl-3-methyl-6, 7-methylenedioxyisoquinoline with R2NH, RNH2 and NH3.2) 1-β-Dialkylaminoethyl-3-methyl-6, 7-methylenedioxyisoquinoline (IV) and bis-(3-methyl-6, 7-methylenedioxyisoquinolyl (1)-ethyl)-alkylamine (V) were obtained by treating β-bromopropionic α′-methyl-β′methoxy-β′-(3, 4-methylenedioxyphenyl)-ethylamide with R2NH and RNH2 (R=CH3 and C2H5) and then cyclizing these products.3) Physiological tests of these compounds showed that antispasmodic action of (II) and (V) was approximately equal to that of papaverine used as a control.

Electric dialysis was carried out on crude iodocasein by dissolving 50g. of it in 2 l. of 0.15% NaOH solution, using porous sheet as the diaphragm. The electric current dropped rapidly from the initial 3amp. to 0.85amp. after which the change became gradual. This shows the process of inorganic ion removal from the solution. Below 0.85amp., the presence of inorganic ion in the solution becomes very small. This state is reached only one or two hours after the start of dialysis. At this stage, the presence of free iodine in the product decreases to less than 0.1%, and becomes almost nil after 2.5hrs. By this means of purification, a product of iodocasein was obtained containing a maximum organic iodine at 7.19%.

Iodocasein obtained by electric dialysis at below 0.85amp. is entirely non-toxic to tadpoles. In this case, the amount of free iodine is below 0.09%. Addition of 5mg. of iodocasein to 150cc. of water in which three tadpoles are kept, results already in shortening of their tails, with a more remarkable change in the decrease of their weight. Administration of 20mg. of iodocasein with 6% free iodine results in its change to a grown frog of 28-30mg. weight. The same administration of iodocasein containing 7% free iodine resulted in a grown frog of 22-23mg. weight by the 11th day, which was about 2/3 the weight (35-38mg.) of the control. This shows that difference of 1% in iodine content gives a large difference in the process of metamorphosis in tadpoles, greater the iodine content giving swifter change. The physiological action of iodocasein is stronger than that of dried thyroid gland powder, being 5-10 times greater. A subcutaneous injection of 1mg. of iodocasein in mice gave no appreciable effect.

General analyses were carried out on the Formosan cobra venom and its fractionation was carried out with ammonium sulfate and acetone. It was found that a certain amount of purification was possible by the simple acetone method. The venom divided into two portions by the acetone method, one, a strong venom (potency, 6.6 times that of the original venom) which possessed a strong lecithinase action and no irritative action against mucous membrane, and the other, a weak one (potency, 1/25 of the original venom) which possessed almost no lecithinase action but a very strong irritative action against mucous membrane. The strong venom was further purified by ammonium sulfate into a very strong venom (potency, 10 times the original) possessing almost no lecithinase action. Both venoms were put to general analyses, and the results of their nitrogen distribution, content of cystine-form sulfur, and total sulfur are shown in the accompanying table. Total and cystine-form sulfur were found less in the strong venom, showing that they are not proportionate to the poison. The contrary evidence was obtained with the nitrogen content, which was found to be larger in a stronger venom. The amount of histidine and arginine nitrogen was the most remarkable, the amount of histidine nitrogen in the strong venom being seven times that in the weak venom. It is interesting to note that this portion showed a strong Pauli reac tion. Since the potency of the venom was lowered by the action of nitrous acid, amino-nitrogen is also related to the poisonous property.

Treatment of 4-nitropyridine-N-oxide with 48% hydrobromic acid at 160° results in the formation of 4-bromopyridine-N-oxide, 4-hydroxypyridine-N-oxide, 3-bromo-4-hydroxypyridine-N-oxide, 3, 5-dibromo-4-hydroxypyridine-N-oxide, 4-hydroxypyridine and 3, 5-dibromo-4-hydroxypyridine, besides a very minute amount of 4-bromopyridine. In other words, 4-bromopyridine-N-oxide is formed at first in this reaction, and this undergoes hydrolysis to 4-hydroxypyridine-N-oxide, followed by bromine substitution and reductive desoxidation of the N-oxide group by hydrobromic acid at high temperatures and compounds as listed above are formed.

In order to examine efficacies as anthelmintics against ascaris, 6-chloro-4-decyl- and 6-chloro-4-dodecylresorcinols were prepared and their physical constants described. These compounds possessed a very low toxicity and hardly any irritating actions but clinical tests revealed that their power to remove ascaris was also very weak.

The toxicities of coumarin, 2-thiocoumarin and 4-methylcoumarin were determined with mice by the method of calculations postulated by Behrens-Kärber and Van der Waerden. It was found that coumarin was the most toxic, followed by 2-thio- and 4-methyl-coumarin. Various methods of calculating LD50, viz. Behrens-Kärber's, Van der Waerden's and Bliss', were compared for their precision and practicability and found that Van der Waerden's method was the most suitable for a routine assay.

1) By the application of dimethylamine or diethylamine on β-bromethylidene diethyl ether, dimethyl- or diethyl-aminoacetal was obtained in a good yield.2) Grignard reagent was applied on 2-benzylideneamino- and 5-chloro-2-benzylideneamino-pyridines to form addition products which were condensed with β-dimethylaminoethyl or β-diethyaminoethyl chloride to obtain four kinds of pyribenzamine compounds.

p-Nitro-α-acylaminoacetophenone was prepared from either p-nitroacetophenone oxime p-tolyl ester by a method similar to the Beckmann rearrangement reaction or by introducing p-nitrobenzoyl group into 2-phenyl-5 (4H)-oxazolone. By aldol condensation, the Pondorff's reduction, hydrolysis and dichloroacetylation of the above compound, dl-chloramphenicol was obtained.

By the condensation of 1-phenyl-1-methoxy-2-nitroethane and paraformaldehyde, 1-phenyl-1-methoxy-2-nitro-3-propanol was obtained which was reduced, acylated, nitrated and hydrolyzed to threo-1-p-nitrophenyl-2-amino-1, 3-propane-diol. As the by-products of this reaction, compounds of erythro series were isolated.

By the combination of d-tartaric acid with dl-threo-1-p-nitrophenyl-2-amino-1, 3-propanediol in water or methanol, its tartrate insoluble in water was collected. This salt was freed by alkalis to d-(-)-threo-1-p-nitrophenyl-2-amino-1, 3-propanediol, and acylated by dichloroacetic anhydride or dichloroacetic acid to optically active chloramphenicol.